package com.itheima.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * ClassName: LoginCheckFilter
 * Package: com.itheima.reggie.filter
 * Description: 过滤器：检查当前用户是否完成了登录,如果没有登录则跳转到登录页面
 *
 * @Author www.youkewang.top
 * @Create 2023-10-22 22:41
 * @Version 1.0
 */
@WebFilter(filterName = "loginCheckFilter", urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {

    // 路径匹配器,支持通配符, Spring核心包自带的工具类
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        // 1、获取本次请求的URI
        String requestURI = request.getRequestURI();
        // 定义需要放行路径的白名单
        String[] urls = new String[]{"/employee/login", "/employee/logout", "/backend/**", "/front/**", "/common/**", "/user/sendMsg", "/user/login"};

        //log.info(requestURI);

        // 2、判断本次请求是否需要处理
        boolean isMatch = check(urls, requestURI);


        // 3、如果不需要处理，则直接放行
        if (isMatch) {
            //log.info("本次请求{}不需要处理", requestURI);
            // 放行当前请求
            filterChain.doFilter(request, response);
            return;
        }

        // 4、判断登录状态，如果已经登录，则直接放行
        if (request.getSession().getAttribute("employee") != null) {
            //log.info("用户已登录，用户id为: {}", request.getSession().getAttribute("employee"));

            Long empId = (Long) request.getSession().getAttribute("employee");
            // 把用户的session数据放到线程对象中
            BaseContext.setCurrentId(empId);

            long id = Thread.currentThread().getId();
            //log.info("线程ID为: {}", id);

            filterChain.doFilter(request, response);
            return;
        }

        // 判断移动端用户登录状态
        if (request.getSession().getAttribute("user") != null) {
            //log.info("用户已登录，用户id为: {}", request.getSession().getAttribute("user"));

            Long userId = (Long) request.getSession().getAttribute("user");
            // 把用户的session数据放到线程对象中
            BaseContext.setCurrentId(userId);

            long id = Thread.currentThread().getId();
            //log.info("线程ID为: {}", id);

            filterChain.doFilter(request, response);
            return;
        }

        // 5、如果未登录则返回未登录结果,通过输出流的方式向客户端页面响应数据
        //log.info("用户未登录");
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;

        //log.info("拦截到请求: {}", request.getRequestURI());

    }

    /**
     * 路径匹配，检查本次请求是否需要放行
     *
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls, String requestURI) {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match) {
                // 匹配成功
                return true;
            }
        }
        return false;
    }
}
